Mark the letter A, B, C or D to indicate the sentence that best combines the following pairs of sentences.Câu hỏi "The teacher is very kind. She helped me with my project." A. The teacher whose helped me with my project is very kind. B. The teacher which helped me with my project is very kind. C. The teacher who helped me with my project is very kind. D. The teacher whom helped me with my project is very kind.